A system and method for determining the effectiveness of marketing content

A method of determining marketing effectiveness comprising matching recorded customer transactions 22 with access to marketing content 24 made by the same customer and assigning a value 23 to the marketing content based on the value of the transaction. A customer score is calculated for each item of marketing content by combining all assigned values for that item 26, a performance score being calculated based on the customer score and the number of times the marketing content has been accessed 29. The value assigned may be based on profit or total transaction value. Thus the performance value will include users who viewed the marketing material but did not make a purchase. A time period may be selected 21 for the analysis. Marketing items accessed but not matching any transaction may be excluded from consideration or given a performance score of zero. A user accessing marketing items and making purchases using different devices may be identified and the actions linked using behaviour analysis. Records of customer actions may be anonymous.